/Engine/Plugins/FX/Niagara/Source/Niagara/Public/NiagaraComponent.h
Clear any active simulation cache. When clearing a simulation cache that has been running you may wish to reset or continue, this option is only valid when using a full simulation cache. A renderer only cache will always reset as we can not continue the simulation due to missing simulation data.
[UFUNCTION](Programming/UnrealArchitecture/Reference/Functions)(BlueprintCallable, Category=SimCache) void ClearSimCache ( bool bResetSystem )